diff --git a/platformio.ini b/platformio.ini
index 41287a9a6..4e0f3a925 100644
--- a/platformio.ini
+++ b/platformio.ini
@@ -263,7 +263,7 @@ lib_ignore = iLabs Hearth
 extends = arduino_base
 ; RadioLib's pinned STM32WL HAL uses the Arduino 2.x GPIO API. STM32 platform
 ; 20 / Arduino 3 changes those signatures; keep release builds reproducible.
-platform = ststm32@19.4.0
+platform = ststm32@19.5.0
 extra_scripts = post:arch/stm32/build_hex.py
   post:scripts/check_firmware_ram.py
 build_flags = ${arduino_base.build_flags}
diff --git a/test/test_stm32_float_conversion.py b/test/test_stm32_float_conversion.py
index f8ab443b6..1dc3f8446 100644
--- a/test/test_stm32_float_conversion.py
+++ b/test/test_stm32_float_conversion.py
@@ -13,7 +13,7 @@ class Stm32FloatConversionTest(unittest.TestCase):
     def test_stm32_platform_keeps_the_supported_radiolib_gpio_api(self):
         config = configparser.ConfigParser(interpolation=None, strict=False)
         config.read(ROOT / "platformio.ini")
-        self.assertEqual(config["stm32_base"]["platform"], "ststm32@19.4.0")
+        self.assertEqual(config["stm32_base"]["platform"], "ststm32@19.5.0")
 
     def test_signed_values_and_limits_without_ltoa(self):
         with tempfile.TemporaryDirectory() as directory: